1. Field of the Invention
The invention relates to bicycles for exercise and/or therapeutic purposes.
2. Description of the Related Art
The bicycle has been tremendously successful not only as a form of transportation, but for exercise purposes as well. The term bicycle used in this context includes road bikes as well as stationary bikes. In the marketplace, road bikes and stationary bikes have proven to be extremely successful. Literally tens of millions of both road bikes and stationary bikes are used on a regular basis which demonstrates not only the popularity of the bicycle as a machine per se, but also the general interest of the population in using machines for exercise, conditioning and therapeutic purposes.
In this regard, the proliferation and success of a myriad of exercise machines has been extensive over the last two decades. This proliferation coincides with an increased awareness in the community of health consciousness, physical conditioning, and a sense of well-being from exercise.
The road bike and stationary bike, however, have remained a very popular alternative for exercise and rehabilitation. There have been no significant technological or structural changes to the bicycle over the past decades. Inherent in the concept of the bicycle as a machine is the creation of efficiency, i.e., to reduce the workload required to perform a certain function. The stationary bicycle continues to use a single drive sprocket (may or may not include a flywheel) joined by a single axle having two cranks coupled 180 degrees out of phase with each other while utilizing various types of resistance. The resistance and work output are related to the amount of resistance applied to the cranks. Of great interest to the exercise community, both for exercise and therapeutic purposes, is the ability to maximize work output per unit time. An example of an attempt to expand work output as well as expanding the physical demands on an increased number of muscles can be seen in an aerodyme bike. The aerodyme bike requires pedaling while simultaneously exercising the upper body with the use of crank arms.
In reference to the muscles worked during bicycling, the extensor muscles, i.e., the quadriceps and hip extensors are essentially emphasized. During pedaling, most of the work output is created on the downstroke with momentum while the opposite pedal takes the leg through the upstroke with a much reduced work demand. Experienced professional riders learn to push and pull to maximize their workload during short bursts, but even in this regard, the upstroke pedal is still assisted by the opposite downstroke pedal.
Herein is where the deficiency lies. When someone with an injury in one leg wants to use a road bike or a stationary bike, one leg is dependent on the other because normal bicycles are bipedal. In other words, the injured leg can not be independently worked without the use of the other leg. Furthermore, current bicycle operations are efficient while only working specific muscle groups in the leg. Hence, the user does not have an option to simultaneously exercise both the agonist and antagonist muscles through the cycle of rotation, i.e., quad and hamstrings, hip flexors and hip extenders.
It would be an improvement on the current art to create a unipedal cycle wherein each leg's movement is independent of the other. This aspect would serve to expand the effectiveness of bicycling in reconditioning of an injured leg. Independent operation of the legs would also increase the work output demands per unit time but not at the expense of overstressing the joints, muscles and soft tissues. It would be counterproductive if additional injuries were created. A device that overcomes the shortcomings as just described for a road bike or stationary bike is not disclosed in the prior art.